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Nuclear Fusion

((Author’s Note: According to the comments below, this article is nothing more than the nonsensical ravings of a lunatic mind, everything is totally inaccurate, and fusion power is a complete waste of time. Just thought I save you the time.))

In light of the meltdown of the fission nuclear reactor at Fukushima, I thought I talk about Nuclear Fusion power. I wish I could talk about this in good times. However now is the time to talk about this; since it is topical. Please keep in your thoughts and pray for the people of Japan.

I’d like to note that nuclear fission is still safe. More so today than a few decades ago. It took a very powerful earthquake to cause catastrophic damage to the reactor at Fukushima. It would not have failed otherwise. In no way am I advcating an end to nuclear power at this time.Fission vs Fusion

Fission power is the beta-decay of some metals, like plutonium-239 or uranium-235. The decay of fissile isotope creates heat and we turn that heat into usable energy, by heating water and using steam turbines. The fissile isotope’s “half-life” is also the rate at which it decays. Right now, I’m simplifying all of this for you.

So what is fusion? Well, look up in the sky today and you will the largest fusion reactor already in operation: The Sun

Hydrogen atoms are flying around in the Sun and fusing together to create helium. Now it’s a little more complex than that, but the basic idea for a Nuclear Fusion Power Plant is to create a miniature suns on Earth to produce power for us.

Reader: Holy Hell Gator! Creating small suns on earth? What are you thinking? Are you crazy?

Calm down. I’m only simplifing now because this is an introduction. But yeah, that’s the basic upshot of a Fusion Power Plant to generate power. We are going to smash two hydrogen atoms together in create usable enegry here on Earth.

According to the Lawson criterion, the easiest and most promising reaction fuel for fusion, is the D-T Fuel Cycle. The D-T stands for: Deuterium and Tritium.

Both Deuterium (H-2) and Tritium (H-3) are hydrogen isotopes. While deuterium is readily available, tritium is not because of it’s half-life of 12.32 years. However the deuterium-tritium fuel cycle requires the breeding of tritium from lithium and since we have tons of lithium here on earth, we have the potitional to power mankind with Fusion Power (using this fuel cycle) for 6,000 years.

It’s amazing and exciting stuff. Again, I am sorry I am talking about this in such long shadows right now.

We could use a D-D Fuel Cycle, but that takes a higher tempature reaction and since lithium can double as a coolant, it is consider more difficult to facilitate.

Accident Potential

Since the disaster at Fukushima, this is most likely the most important part:

There is no possibility of a catastrophic accident in a fusion reactor resulting in major release of radioactivity to the environment or injury to non-staff, unlike modern fission reactors. The primary reason is that nuclear fusion requires precisely controlled temperature, pressure, and magnetic field parameters to generate net energy. If the reactor were damaged, these parameters would be disrupted and the heat generation in the reactor would rapidly cease. In contrast, the fission products in a fission reactor continue to generate heat through beta-decay for several hours or even days after reactor shut-down, meaning that melting of fuel rods is possible even after the reactor has been stopped due to continued accumulation of heat.

There is also no risk of a runaway reaction in a fusion reactor, since the plasma is normally burnt at optimal conditions, and any significant change will render it unable to produce excess heat. In fusion reactors the reaction process is so delicate that this level of safety is inherent; no elaborate failsafe mechanism is required. Although the plasma in a fusion power plant will have a volume of 1000 cubic meters or more, the density of the plasma is extremely low, and the total amount of fusion fuel in the vessel is very small, typically a few grams. If the fuel supply is closed, the reaction stops within seconds. In comparison, a fission reactor is typically loaded with enough fuel for one or several years, and no additional fuel is necessary to keep the reaction going.

In the magnetic approach, strong fields are developed in coils that are held in place mechanically by the reactor structure. Failure of this structure could release this tension and allow the magnet to “explode” outward. The severity of this event would be similar to any other industrial accident or an MRI machine quench/explosion, and could be effectively stopped with a containment building similar to those used in existing (fission) nuclear generators. The laser-driven inertial approach is generally lower-stress. Although failure of the reaction chamber is possible, simply stopping fuel delivery would prevent any sort of catastrophic failure.

Most reactor designs rely on the use of liquid lithium as both a coolant and a method for converting stray neutrons from the reaction into tritium, which is fed back into the reactor as fuel (see D-T Fuel Cycle above). Lithium is highly flammable, and in the case of a fire it is possible that the lithium stored on-site could be burned up and escape. In this case the tritium contents of the lithium would be released into the atmosphere, posing a radiation risk. However, calculations suggest that the total amount of tritium and other radioactive gases in a typical power plant would be so small, about 1 kg, that they would have diluted to legally acceptable limits by the time they blew as far as the plant’s perimeter fence.

I don’t remember where I got this, but I have it written down on my computer on a text file.

To boil that all down: It takes such delicate conditions to create a fusion reaction, that a loss in these conditions will see an auto shut-down in the fusion reaction. Even if tritium does leak out, its half-life is only 12.32 years. Compare that to plutonium-239’s half-life of about 24,200 years.

Drawbacks

I will not lie to you. There are drawbacks right now.

The first tokamak fusion power plant won’t come online until 2035 and it will be in Europe. It is a “commercial demonstrator” and thus other power plants will take even longer to come online. Truth of the matter, we will never see a fusion power plant in the US in our life-time.

Also, to start a reaction in a tokamak power plant takes a fission ignition (note: it takes a fusion ignition to blow up a fission bomb, ironic no?). We clearly need a better ignition source.

Future Power

Fusion Power is an energy source of the future. Unless they cure aging and death, we will not see the pure awesomeness of this truly amazing power. However this does not mean we should stop our efforts in advancing research in fusion power. There are some things, like fusion, worth spending money on. Everything we do now should be for the future. And I see a future in the Tokamak Nuclear Fusion Power Plant as large scale power source and the Hydrogen Fuel Cell as a small, mobile power source (like for cars).

That said, I do not see a future for Solar or Wind Power. They are bulky and produce very little energy. This is why I don’t believe in spending money on researching these so-called sources of power, because they are a waste of time.

Still, it is 2011 and not 2035. In the meantime, we should not be scared of drilling for our very own oil or use current (and still very safe) nuclear energy. My car still uses gas. We are dying out here on the pump. Time to lift the oil drilling moratorium on deep-sea and onshore drilling. Time to build more oil refineries. Do something, Obama.